Embodiments of this disclosure relate generally to a grease shield, and more particularly, to a shield that allows grease to be retained in a constant velocity joint with high articulation angles wherein the shield consists of a series of rings that overlap one another in an outer case that allows the rings to rotate with an axle and articulate at high angles.
A universal joint is a mechanical coupling device that provides a rotational driving connection between two rotatable shafts, while permitting such shafts to be oriented at an angle relative to one another. Universal joints are commonly used in the drive train systems of vehicles. For example, universal joints are often used to rotatably connect a driveshaft tube between an output shaft of an engine/transmission assembly or other source of rotational power and an input shaft of an axle assembly including a pair of driven wheels.
The current art for a constant velocity joint grease shield does not provide a barrier that retains the grease in the constant velocity joint on vehicles that require high articulation angles of the axle. This results in the grease spinning out of the constant velocity joint and into the boot upon acceleration. This causes the joint to dry out, which leads to premature wear of the constant velocity joint.
One solution to the above issue as disclosed in U.S. Pat. No. 6,579,187, issued to John A. Ramey. Ramey discloses a barrier for use in a constant velocity joint wherein the constant velocity joint has a lubricant within an outer race and a boot secured to a boot cover. The barrier includes a shield wherein that shield is in contact with the outer race and the boot cover. The shield generally has a body with a cup shaped cross section and a circumferential flange extending therefrom. The shield provides a barrier between the boot and the heat and grease lubricant of the constant velocity joint. However, the Ramey design only works in vehicles that do not require high articulation angles.
Further, in the past these shields have been made out of rubber. This allowed the axle to move but only as far as the tolerances of the rubber seal. In the existing art excessive deflection would cause the seal to tear. The other problem associated with the existing art is that the rubber would crack over time with the exposure to the elements, grease and constant deflection and heat.
Therefore, it would be desirable to provide a device and method that overcomes the above problems.